Abstract: The problem of recovering from multiple link failures in a way that is quick, avoids loops, avoids packet modifications, and that avoids significant modifications to existing routers is solved by: (1) associating a network rerouting unit (NRU) with each of the plurality of routers; (2) configuring each router so that if a link (or more specifically, any link) directly connected to the router fails, the router redirects any packets whose next hop is a port terminating an end of the failed link to the NRU associated with the router; (3) executing a routing protocol on each of the NRUs whereby each NRU will learn a topology of the communications network; (4) receiving by a first NRU, a packet redirected from the router associated with the first NRU; and (5) responsive to receiving, by the first NRU, the packet redirected from the router associated with the first NRU, (i) identifying a link directly connected to the router as a failed link using a destination address in the redirected packet, and the topology of

Abstract: The claimed subject matter is directed to novel methods and systems for a network topology wherein an Internet Protocol (IP) network is partially integrated and enhanced with a relatively small number of Software Defined Network (SDN)-Openflow (SDN-OF) enabled network devices to provide a resilient network that is able to quickly recover from a network failure and achieves post-recovery load balancing while minimizing cost and complexity. The SDN-OF Controller, or a management node, determines such a minimum set of SDN-OF enabled devices and establishes IP tunnels to route traffic from nodes affected by failure to designated SDN-OF switches and finally to the final destination without looping back to the failed link or node. By combining SDN-OF enabled switches with IP nodes such as routers, a novel network architecture and methods are described herein that allows for ultra-fast and load balancing-aware failure recovery of the data network.

Abstract: A network controller comprising a processor configured to obtain topology information of a network, wherein the topology information indicates a plurality of non-software-defined networking (non-SDN) network elements (NEs) interconnected by a plurality of links in the network, analyze each non-SDN NE according to the topology information to determine whether the non-SDN NE is a candidate NE for establishing a backup tunnel to protect a single-link failure at one of the plurality of links, and select a plurality of target NEs from the candidate NEs to protect against all single link-failures in the network, and a transmitter coupled to the processor and configured to send a first message to a first of the target NEs to dynamically enable software-defined networking (SDN) functionalities at the first target NE in order to facilitate single-link failure protection in the network.

Abstract: The problem of recovering from multiple link failures in a way that is quick, avoids loops, avoids packet modifications, and that avoids significant modifications to existing routers is solved by: (1) associating a network rerouting unit (NRU) with each of the plurality of routers; (2) configuring each router so that if a link (or more specifically, any link) directly connected to the router fails, the router redirects any packets whose next hop is a port terminating an end of the failed link to the NRU associated with the router; (3) executing a routing protocol on each of the NRUs whereby each NRU will learn a topology of the communications network; (4) receiving by a first NRU, a packet redirected from the router associated with the first NRU; and (5) responsive to receiving, by the first NRU, the packet redirected from the router associated with the first NRU, (i) identifying a link directly connected to the router as a failed link using a destination address in the redirected packet, and the topology of

Abstract: A network controller comprising a processor configured to obtain topology information of a network, wherein the topology information indicates a plurality of non-software-defined networking (non-SDN) network elements (NEs) interconnected by a plurality of links in the network, analyze each non-SDN NE according to the topology information to determine whether the non-SDN NE is a candidate NE for establishing a backup tunnel to protect a single-link failure at one of the plurality of links, and select a plurality of target NEs from the candidate NEs to protect against all single link-failures in the network, and a transmitter coupled to the processor and configured to send a first message to a first of the target NEs to dynamically enable software-defined networking (SDN) functionalities at the first target NE in order to facilitate single-link failure protection in the network.

Abstract: The claimed subject matter is directed to novel methods and systems for a network topology wherein an Internet Protocol (IP) network is partially integrated and enhanced with a relatively small number of Software Defined Network (SDN)-Openflow (SDN-OF) enabled network devices to provide a resilient network that is able to quickly recover from a network failure and achieves post-recovery load balancing while minimizing cost and complexity. The SDN-OF Controller, or a management node, determines such a minimum set of SDN-OF enabled devices and establishes IP tunnels to route traffic from nodes affected by failure to designated SDN-OF switches and finally to the final destination without looping back to the failed link or node. By combining SDN-OF enabled switches with IP nodes such as routers, a novel network architecture and methods are described herein that allows for ultra-fast and load balancing-aware failure recovery of the data network.

Abstract: A multimedia bitrate adaption method for individual users wherein only a set of predetermined bitrates may be selected as the multimedia bitrate of the user. The predetermined bitrates are quantized into exponentially distributed levels, and the users' experiences corresponding to the predetermined bitrates are with the same intervals, thereby increasing the service capacity and improving user satisfaction.

Abstract: The claimed subject matter is directed to novel methods and systems for a network topology wherein an IP network is partially integrated and enhanced with a relatively small number of SDN-OF enabled network devices to provide a resilient network that is able to quickly recover from a network failure and achieves post-recovery load balancing while minimizing cost and complexity. By combining SDN-OF enabled switches with traditional IP nodes such as routers, a novel network architecture and methods are described herein that allows for ultra-fast and load balancing-aware failure recovery of the data network.

Abstract: A multimedia bitrate adaption method for individual users wherein only a set of predetermined bitrates may be selected as the multimedia bitrate of the user. The predetermined bitrates are quantized into exponentially distributed levels, and the users' experiences corresponding to the predetermined bitrates are with the same intervals, thereby increasing the service capacity and improving user satisfaction.